Manufacture of electrical rectifiers



the temperature of the second furnace.

Patented June 23, 1931 UNITED STATES PATENT OFFICE DONALD G. AGKERLY, OFEDGEWOOD BOROUGH, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNALCOMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORA- TION OF PENNSYLVANIAMANUFACTURE OF ELECTRICAL REGTIEIERS No Drawing.

My invention relates to the manufacture of electrical rectifiers of thetype disclosed and claimed in Letters Patent of the United States, No.1640335, granted to L. O. Gron- 4? dahl on August 23, 1927.

One object of my invention is the provision of novel and improved meansfor producing metallic copper on the outer surface of the copper oxidein rectifiers of the type referred The treated blank is then placed in abath of molten metal to reduce the outer layer of the oxide to copper.This molten metal may, for example, be molten lead, in whichcase thebath should be at a temperature of 500 C. to 600 C. The purpose ofproducin the layer of copper on the outer surface 0 the copper oxide is,of course, to make it possible to readily make electrical contact withthe cuprous oxide.

ide rectifiers involves removing the treated blanks from the oxidizingfurnace to a second furnace maintained at approximately 500 to 600 (3.,and quenching the blanks in water after they have reached approximagalyne reason for maintaining the reducing bath of my invention at 500 to600 C. is to make this bath serve the purpose also of the secondfurnace, so that the blanks may be uenched in water directly from thereducin ath.

Although I have herein describe onlyone rocess of manufacturingelectrical rectifiers, it is understood that various changes andmodifications may be made therein within the scope of the appendedclaims without departing from thespirit and scope of my invention.

Having thus described my invention, what I claim is:

J 1. The process of producing a rectifier unit The prefered heattreatment of copper ox- Application filed September 11, 1929. Serial No.891,985.

which consists in treating a copper blank to form cuprous oxide thereon,and then placmg the treated blank in a bath of molten metal to reducethe outer surface of the oxide to copper.

2 The process of producing a rectifier unit which consists in treating acopper blank to form cuprous oxide thereon, and then placing the treatedblank in a bath of molten lead to reduce the outer surface of the oxideto copper.

3 The process of producing a rectifier unit which consists in treating acopper blank to form cuprous oxide thereon, and then placing the treatedblank in a bath of'lead at a temperature of 500-C. to 600 C. to reducethe outer surface of the oxide to copper.

4;. The process of producing a rectifier unit which consists in treatinga copper blank to form cuprous oxide thereon, placing the treated blankin abath of molten metal to reduce the outer surface of the'oxide tocopper, and then quenchin the blank.

5. The process 0 producing a rectifier unit which consists in heating acopper blank to approximately 1000 C. to form cuprous oxide thereon,placing the treated blank in a bath of molten metal maintained atapproximately 500 to 600 C. to reduce the outer surface of the oxide tocopper, and then quenching the blank.

In testimon whereof I aflix my si ature.

DONALD G. ACKE LY.

